Color Fastness to Rubbing
In dyed and printed textile materials the unfixed color particles are mechanically hung at first glance and these particles are rubbed off effectively on the wearer skin or some other cloth of contact. So it is important to decide the rubbing quickness of dyed or printed textile materials. Rubbing is the transference of shading from hued textile material to different surfaces mainly by rubbing.
The rubbing speed can be dictated by utilizing an instrument called crockmeter and it chips away at the guideline of scraped spot. At the point when the crockmeter finger with test texture slides over the example because of contact there is shading exchange from the hued example to the white crocking cloth. Because of the scraped area the profound dyed fibers break into small scale fibrils and stick onto the crocking cloth for all time. Rubbing can happen under dry and wet conditions.
In dry rubbing, at first the fringe of the shaded example get burst, so that the freely or unfixed color particles are evacuated and clung to the surface fibers of the crocking cloth. At first the centralization of the color stuff is all the more, so all the more recoloring happens and there are more surface fibers in the crocking cloth that can hold color or shade particles. As the rubbing cycle proceeds because of scraped spot the surface fibers are expelled as profound dyed small scale fibrils in dull shade.
In wet rubbing, unfixed colors will break up in water and after that it is exchanged to the test texture, henceforth bringing about poor wet rubbing speed. In wet crocking both shading and the hued short fibers are exchanged to the crocking cloth. In the standard vessel meter around 9N of load is connected with a finger width of 16 mm which slides over the track length of 104mm which slides around 10 cycles for each 10 sec.
Colour Fastness to Rubbing Test Method
In ISO-105-X12 the wet pickup of the rubbing cloth is 100% .While in AATCC-08 the wet Pickup of the rubbing cloth is 65%.We check rubbing by Dry and Wet techniques. In wet rubbing we wet the rubbing cloth as per test strategy and give rating by contrasting the Staining and the dim scale.
Essentially for dry rubbing we check the rubbing with dry rubbing cloth and contrast the recoloring and dark scale for evaluations. Shading Fastness to rubbing is a fundamental test which is constantly required for each hued texture it is possible that it is Printed or dyed.
On the off chance that the shading quickness to rubbing is great then its different properties like Washing speed and toughness and so on enhances naturally on the grounds that the rubbing is a strategy to check the obsession of the shading on the texture. So if the obsession is great its washing properties will be great.
Rubbing Fastness relies upon:
- Nature of the Color
- Profundity of the Shade
Development of the Fabric Nature of the shading Each shading it is possible that it is color, Reactive, Disperse or direct has its own particular quickness properties to rubbing. There are a few hues like dark, Red, Burgundy, Navy blue which have poor Color quickness properties as a result of their concoction structure.
Like Black shading is a carbon base shading and the molecule size of carbon is extensive than alternate hues that are the reason its rubbing properties are poor. Also red and blue are in a similar case. So to enhance the shading quickness we add more folio to enhance the speed properties of these hues. It doesn’t imply that we can not accomplish the best outcomes with these hues. The required outcomes can accomplish yet creation cost will be increment. Then again the development of the texture likewise impacts the quickness properties.
In the event that the rubbing speed on 100.80/40.40 is 3 on the dark scale, it will be 2-3 on 52.52/22.22 with a similar printing parameter. So dependably remember these impacts amid conclude the required parameters with your client.
Continuously Check
- Quality development
- Color
- Depth of the Color
- End Use of the item
Comes about which we can accomplish in Normal Conditions are
| Dark Shade | Medium shades | Light Shades | |
| Dry | 3-4 | 4 | 4-5 |
| Wet | 2-2.5 | 3 | 3.5-4 |
The Factors Affecting Color Fastness
1. Material Characteristics:
The attributes of the textile materials like the nature of fiber or yarn and the texture surface structure assume a vital part in choosing the rubbing quickness.
Cotton is the most broadly utilized textile fibers on the planet representing over half of aggregate utilization. There ought to be an appropriate determination of cotton fiber to guarantee great rubbing speed. Whenever juvenile and dead cotton fibers are utilized, amid turning it experiences scraped area with metallic parts and the youthful fibers may break into short fibers. Facilitate in coloring the dyes won’t be appropriately settled to the youthful and dead fibers. In this way, develop cotton fibers can be improved the rubbing quickness.
The checked yarn has all the more short fibers, amid wet rubbing both shading and hued short fibers are exchanged to the crocking cloth. Consequently, we can pick brushed yarn where the short fiber substance is less. The open end turning yarns like rotor yarn has all the more short fibers so we can go for ring\compact yarn.
It has been discovered that the texture made out of mercerized cotton indicates enhanced quickness to rubbing. Because of the adjustment in the fiber structure on mercerizing, there is a 30% less degree of evacuation of fiber particles.
These jutting fibers spotted over the surface can be evacuated by bio cleaning. Cellulose catalysts are utilized to debase the raised fiber or yarn. At the point when these proteins are connected to the texture, they mostly process the distending fibers and extricated from the texture. The extricated fiber or yarn is then expelled by rapid mechanical disturbance.
The surface structure of the textile materials impacts the rubbing speed to a degree. at the point when the crocking finger slides over the example, there will be a contact zone between the two surfaces (ostensible contact area).However every one of the purposes of the crocking cloth won’t touch the example, the contact happens at the tip of the intersection (genuine contact area).The ostensible contact range is same for a wide range of textures yet the genuine contact territory shifts from texture to texture.
In the event that a dyed cotton texture is utilized as an example, there will be surface fibers in the middle of the twist or weft yarns. So the genuine contact range is all the more, consequently, there is a probability of more shading exchange from the example to the crocking cloth. For engineered fibers, the measure of surface fibers is less relatively with cotton textures. On the off chance that the surface is unpleasant the scraped spot is progressively and there is a probability of poor rubbing quickness. So smooth surface gives great rubbing quickness.
2. Determination of dyes/Depth of shade:
The determination of color is a fundamental component to guarantee phenomenal rubbing quickness. The determination of color ought to be done on the premise of the partiality of the color atoms to the fiber particles.
For cellulosic fibers, the dyes of long planar atoms are chosen with at least one solubilising gatherings. For engineered polymeric fiber, the color is picked in view of the ionic gatherings in the fiber particles. The polyamide fibers are cationic in nature, so dyes of anionic nature are reasonable. While acrylics are anionic in nature, so the cationic dyes are appropriate. For cellulose acetic acid derivation and polyester fibers, the dyes of at least one polar gatherings must be available. Typically synthetic fibers have great partiality to dyes having short alkyl chains.
Dissolvability is basic for a color to infiltrate into the intermolecular micropores of the fiber. The extent of the color atoms ought to be littler than the pores of the fiber particle so it enters into the inside of the fibers. Else it will stay on the surface of the fiber and get evacuated while on rubbing. The solvency has likewise an unfavorable impact that it causes recoloring while wet crocking.
The profundity of shade decides the appraisals of rubbing speed of the textile materials. The profundity is high because of the more measure of color statement (or) because of the quality of the optical impact created by the color. Because of this reason, the darker shade will container more than the lighter shade.
3. Coloring/printing system (or) obsession of color:
The off base coloring technique and disgraceful obsession are the significant reason for poor crocking.
Because of ineffectual desizing, amid preparing the starch film breaks and the splitting of starch happen. Because of the scraped spot, of dyes present at these spots are released into the handling shower. The released indigo color may redeposit over the surface .This procedure is gotten back to recoloring. As a result of back recoloring the re-stored indigo color won’t be settled to the surface. So it prompts poor crocking. The back recoloring can be controlled by
- The ph of 6.5 to 7.5 ought to be kept up amid handling .
- Lengthing the washing time will diminish the back recoloring.
- Dispersing specialists can be utilized to limit the back recoloring. Ideal dose of 0.5 to 2 gpl of greasy alcohols can be utilized.
- After treatment with protease based cleansers can control back recoloring.
- The completing formulas are accessible to enhance the rubbing speed of indigo dyed denim.
To enhance the dry rubbing speed, the silicone conditioners are utilized. At the point when the large scale emulsions of silicone conditioners are utilized, these full scale emulsions of silicone particles get kept at first glance and give surface delicate quality. The completing layer will keep the grip of the two rubbing surfaces (crocking cloth and the example)
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Aside from the above-examined variables the testing parameters impact to the slightest degree. In the testing of rubbing speed of textile materials, the example is held by test holder to dodge slippage. In light of the condition, the example is held (tight or slack) the color relocation from the specimen to the crocking cloth changes. When it is held at slack condition even at connected load the pleat will add to the genuine contact territory. It requires some frictional constraint to shear the severities (yarn crown) in view of this there will be freedom or evacuation of color particles.
At the tight or extended condition, the stature of the pleat gets diminished because of the pressure in the yarns and the creases get packed towards the textured surface. so the quantity of ill tempers get expanded thusly there is an expansion in the genuine contact zone, the frictional constraint required to shear the severities is more, there is a possibility of freedom of color particles is more.For a similar specimen the relocation of shading to the crocking cloth changes by the condition the example is held.
From the above exchange, it can be presumed that rubbing speed relies on upon variables like material qualities, Selection of dyes/profundity of shade, Dyeing \ printing strategy.It is certain that the chose test ought to contain less short fibers, by legitimate soaping and by great obsession, we can enhance the rubbing quickness of textile materials. However, the rubbing quickness of printed and dyed merchandise can be enhanced via precisely taking care of the above variables.
Colorfastness to Crocking AATCC Test Method 8-1996
- Reason and Scope
1.1 This test strategy is intended to decide the measure of shading exchange red from the surface of hued textile materials to different surfaces by rubbing. It is material to textiles produced using all fibers as yarn or texture whether dyed, printed or generally shaded.
1.2 Test systems utilizing white test cloth squares, both dry and wet with water, are given.
- Rule
2.1 A hued test example is rubbed with a white vessel test cloth under controlled conditions.
2.2 Color exchanged to the white test cloth is surveyed by a correlation with the Gray Scale for Staining (AATCC Evaluation Procedure 2) or the AATCC 9-Step Chromatic Transference Scale (AATCC Evaluation Procedure 8) or Instrumental Assessment of Degree of Staining (AATCC Evaluation Procedure 12), and a review is doled out.
- Wording
3.1 colorfastness, n.— the resistance of a material to change in any of its shading attributes, to exchange of its colorant(s) to nearby materials, or both, subsequently of the presentation of the material to any condition that may be experienced amid the handling, testing, stockpiling or utilization of the material.
3.2 crocking, n.— an exchange of colorant from the surface of a hued yarn or texture to another surface or to an adjoining territory of a similar texture mainly by rubbing.
- Security Precautions
4.1 Good laboratory practices ought to be taken after. Wear security glasses in all laboratory territories.
- Utilizations and Limitations
5.2 Since washing, cleaning, shrinkage, pressing, completing, and so forth may influence the level of shading exchange from a material, the test might be made some time recently, after, or prior and then afterward any such treatment.
- Apparatus and Materials (see 14.1)
6.1 What is a Crockmeter? Crockmeter is also known as motorized crockmeter, rub test machine (see 14.3, 14.4 ).
6.2 Crockmeter Test Cloth, cut in 50 mm squares (see 14.5).
6.3 AATCC 9-Step Chromatic Transference Scale (AATCC Evaluation Procedure 8) (see 14.6).
6.4 Gray Scale for Staining (AATCC Evaluation Procedure 2) (see 14.6).
6.5 White AATCC Textile Blotting Paper (see 14.6).
6.6 Specimen Holder for crockmeter (see 14.4).
6.7 In-house poor crocking cloth.
6.8 Crockmeter Verification Cloth. This item may be used in lieu of an in-house poor crocking cloth when such poor in-house crocking cloth is not available.
- Check
7.1 Verification keeps an eye on the operation of the test and the device ought to be made routinely and the outcomes kept in a log. The accompanying perceptions and remedial activities are critical to stay away from inaccurate test outcomes where irregular vessel pictures can result and impact the rating procedure.
7.2 Use the Crockmeter Verification Cloth or in-house poor crocking fabric with known conduct and direct three dry and wet container tests.
7.2.1 A poor round picture with uneven color get may show the crocking finger needs re-emerging (see 14.7).
7.2.2 A twofold, prolonged picture may demonstrate a free clasp (see 14.7).
7.2.3 An extended and streaked vessel picture might be because of mounting the container square corner to corner.
7.2.4 Scuff imprints to the sides of the example demonstrate the circles to the wire clasps are situated downwards and are not sufficiently high to counteract rubbing the example surface.
7.2.5 A streak in the focal point of the vessel cloth picture and toward rubbing may mean the highest point of the metal base is distorted and not level. This will require abrace embed to square up the analyzer base.
7.2.6 If example holders are utilized, put the holder over the example on the analyzer base. Move the crocking finger on the crocking arm to the most forward position and watch whether it hits within edge of the holder. On the off chance that this happens, advance the holder marginally for all tests. Without adjustment, this issue will bring about a dim range on one side of the crocking picture.
7.2.7 Confirm the wet get strategies (see 10.2).
7.2.8 Replace the rough paper on the analyzer base on the off chance that it is smooth to the touch in the crocking territory contrasted with the contiguous zone, or if slippage of the example is taken note.
7.2.9 In routine testing, watch if various streaks are on the crocking picture. Position example regularly with the long measurement angled to the twist and filling. On the off chance that the course of rubbing falls along a twill line or surface example, and so on., then streaks may happen. On the off chance that they do happen, marginally modify the plot for testing.
- Test Specimens
8.1 Two examples are utilized, one each for the dry and the wet tests.
8.1.1 Additional examples might be utilized to build the accuracy of the normal (see 13.1).
8.2 Cut the examples no less than 50 ×130mm (2.0 ×5.1 in.) and position for testing ideally with the long measurement angled to twist and filling or ribs and courses.
8.2.1 Larger or full width lab tests might be utilized without cutting individual examples, when various tests are required and when utilizing for generation testing.
8.3 Yarns. Weave a bit of texture at least50 ×130 mm, or wind yarn firmly on an appropriate shape no less than 50 ×130 mm with the yarn running in the long course; or generally extended (see 14.8)
- Molding
9.1 Prior to testing, precondition and condition the test examples and the container squares for vessel testing as coordinated in crockmeter ASTM D1776, Standard Practice for Conditioning and Testing Textiles. Condition every example for in any event 4 h in an air of 21 ± 1°C (70 ± 2°F) and 65 ± 2% RH by laying each test example or container square independently on a screen or punctured rack of molding rack.
- Techniques
10.1.2 Place example holder over example as an additional way to forestall slippage.
10.1.3 Mount a container cloth square, the weave parallel with the heading of rubbing, over the finish of the finger which extends descending from the weighted sliding arm. Utilize the uncommon winding wire clasp to hold the test square set up. Position the clasp with circles upward. On the off chance that the circles point descending they can drag against the test example.
10.1.4 Lower the secured finger onto the test example. For manual crockmeters, starting with the finger situated at the front end, wrench the meter handle 10 finish turns at the rate of one turn for each second to slide the secured finger forward and backward 20 times. For electronic crockmeters, set and run the mechanized analyzer for 10 finish turns. Allude to individual details for whatever other required number of turns.
10.1.5 Remove the container cloth square, condition (see 9.1) and assess as coordinated in Section 11. On account of rested, brushed or sanded material when free fiber may meddle with the rating, expel the incidental sinewy material by squeezing softly on the vessel hover with the sticky side of cellophane tap before assessing.
There is a vedio for your reference:https://www.youtube.com/watch?v=WBC5lZioThw&t=8s
10.2.2 Avoid evaporative decrease of the dampness on the vessel square underneath the predefined level of 65 ± 5% preceding the genuine container test is run.
10.2.3 Continue as coordinated in 10.1.
10.2.4 Air dry the container test square, then condition (see 9.1) preceding assessing. On account of rested, brushed or sanded material when free fiber may meddle with the rating, expel the incidental sinewy material by squeezing delicately on the vessel hover with the sticky side of cellophane tape before assessment.
- Assessment (see 14.16)
11.1 Back the crocked test square with three layers of white test cloth for assessing.
11.2 Rate the measure of shading exchanged from the example to the vessel square under examination by methods for the AATCC 9-Step Chromatic Transference Scale (AATCC Evaluation Procedure 8) or the Gray Scale for Staining (AATCC Evaluation Procedure 2) or Instrumental Assessment of Degree of Staining (AATCC Evaluation Procedure 12) and record the numerical rating (see 14.11 and14.14).
11.3 Average the individual outcomes to the closest 0.1 review when numerous examples are tried or when a board of evaluators’ rate shading exchange.
- Report
12.1 State whether dry or wet crocking test.
12.2 Report the review decided in 11.3 to the closest 0.1 review.
12.3 State whether Gray Scale for Staining (EP2), AATCC 9-Step Chromatic Transference Scale (EP8) or Instrumental Assessment of Degree of Staining (EP12) was utilized for assessing recoloring (see 14.6 and 14.9).
12.4 If any pretreatment or after treatment was given to any examples (see 5.2) demonstrate technique for treatment.
- Accuracy and Bias (see 14.15)
13.1 Precision. An interlaboratory test was directed in 1986 to build up the accuracy of the test strategy. Testing was directed under the typical barometrical states of every laboratory and not really under ASTM standard conditions. Two administrators at each of 12 research centers assessed 5 textures in 3 replications by both dry and wet test strategy. Each of 3 raters autonomously evaluated the recolored container squares utilizing both the Gray Scale for Staining and the AATCC 9-Step Chromatic Transference Scale. The first information is on record at the AATCC Technical Center.
13.1.1 The segments of fluctuation as standard deviations of the Gray Scale for Staining or AATCC 9-Step Chromatic Transference Scale rating units are given in Table I.
13.1.2 Critical contrasts are given in Table II.
13.1.3 Example for deciding between laboratory contrasts utilizing one onlooker and the chromatic scale are given in Table III.
13.2 Bias. The genuine estimation of color fastness to crocking must be characterized regarding a test technique. Inside this impediment, this test strategy has no known predisposition.
Table I—Components of Variance
| Test | Wet | Dry | ||
| Scale | Chromatic | Gray | Chromatic | Gray |
| Single Operator/Rater | 0.20 | 0.20 | 0.24 | 0.25 |
| Within Laboratory | 0.20 | 0.19 | 0.31 | 0.34 |
| Between Laboratory | 0.10 | 0.17 | 0.38 | 0.54 |
Table II—Critical Differences
For the parts of change in Table I, two midpoints of watched esteems ought to be considered fundamentally extraordinary at the 95% likelihood level if the distinction parallels or surpasses the accompanying basic contrasts.
| Test | No. of
Observations |
Wet | Dry | ||
| Scale | Chromatic | Gray | Chromatic | Gray | |
| Single Operator/Rater | 1 | 0.55 | 0.54 | 0.68 | 0.70 |
| 3 | 0.32 | 0.31 | 0.39 | 0.40 | |
| 5 | 0.24 | 0.24 | 0.30 | 0.31 | |
| Within Laboratory | 1 | 0.77 | 0.75 | 1.08 | 1.17 |
| 3 | 0.60 | 0.61 | 0.93 | 1.02 | |
| 5 | 0.60 | 0.57 | 0.90 | 1.00 | |
| Between Laboratory | 1 | 0.82 | 0.89 | 1.53 | 1.90 |
| 3 | 0.69 | 0.77 | 1.43 | 1.81 | |
| 5 | 0.66 | 0.74 | 1.41 | 1.79 | |
| The critical differences were calculated using t= 1.96 which is based on infinite degrees of freedom. | |||||
Table III—Crock Test Results
| Wet | Dry | |
| Lab A | 4.5 | 3.5 |
| Lab B | 4.0 | 1.5 |
| Difference | 0.5 | 2.0 |
- Notes
14.1 For potential hardware data relating to this test technique, please visit the online AATCC Buyer’s Guide at http://www.aatcc.org/bg. AATCC gives the likelihood of posting hardware and materials sold by its Corporate individuals, yet AATCC does not qualify, or at all support, underwrite or ensure that any of the recorded gear or materials meets the necessities in its test strategies.
14.2 For rugs, AATCC Method 165, Colorfastness to Crocking: Carpets—Crockmeter Test Method, under the purview of Committee RA57, Floor Covering Test Methods, ought to be utilized.
14.3 The crockmeter gives a reacting to rubbing movement mimicking the activity of a human finger and lower arm.
14.4 The crockmeter is designed to the point that the 16 ± 0.3 mm (0.625 ± 0.01 in.) distance across finger moves forward and backward, with each entire turn of the wrench, in a straight line along a 104 ± 3 mm track on the example, with a descending power of 9 N ± 10% (2 lb ± 10%).
14.5 Crockmeter Test Cloth ought to meet the accompanying details:
- Fiber: 100% 10.3-16.8 mm brushed cotton staple with no optical brightener display
- Yarn: 15 tex (40/1 cotton check), 5.9 turns/cm “z” Thread mean greige texture 32 ± 5 twist closes/cm: 33 ± 5 picks filling/cm
- Weave: 1/1 plain
- Completed texture: desized and blanched with no optical brightener or completing material present
- pH: 7 ± 1
- Mass/sq meter: 100 ± 3 g wrapped up
- Whiteness: W = 78 ± 3 (Method 110)
14.6 The AATCC 9-Step Chromatic Transference Scale, Gray Scale for Staining and the White AATCC Textile Blotting Paper are available from AATCC, P.O. Box 12215, Research Triangle Park NC 27709; tel:+1.919.549.8141; fax:+1.919.549.8933; e-mail: orders@aatcc.org; web site: www.aatcc.org.
14.7 Accidental harm to the rubbing finger, winding clasp or grating paper ought to be repaired as takes after: flawlessly recharge the rough paper; twist the clasp additionally open or closed around a bar somewhat littler in measurement than the vessel peg; restore the finger by development on an additional bit of fine emery cloth in a way mimicking customary utilize.
14.8 For more advantageous vessel testing of different strands of yarn or string a dowel connection is helpful. This connection was created to maintain a strategic distance from the propensity of the standard finger to delve into and push aside the yarns, or slide off them and perhaps give mistaken outcomes. This connection is 25 mm in distance across by 51 mm long. Situated on its side and held set up by the standard finger, it gives a more extensive test region, and holds the white test square by two spring stacked clasps. For extra data on this improvement see the by C. R. Trommer, “Alteration of the AATCC Crockmeter for Yarn Testing,” American Dyestuff Reporter, Vol. 45, No. 12, June 4, 1956, p357; additionally observe s by S. Korpanty and C. R. Trommer, “An Improved Crockmeter for Yarn Testing,” American Dyestuff Reporter, Vol. 48, No. 6, March 23, 1959, p40.
14.9 It has been noticed that distinctive evaluations may come about contingent on whether the Gray Scale for Staining or AATCC 9-Step Chromatic Transference Scale is utilized for the assessment. It is, in this way, critical to report which scale was utilized.
14.10 Experienced administrators don’t need to rehash this measuring strategy amid a test session once the method is set up.
14.11 For exceptionally basic assessments and in instances of mediation, evaluations must be founded on the Gray Scale for Staining.
14.12 For a dialog of vessel testing, see the by J. Patton, “Container Test Problems can be Prevented,” Textile Chemist and Colorist , Vol. 21, No. 3, March 1989, p13; and “Testing for Crocking: Some Problems and Pitfalls”by Allan E. Gut, Textile Chemists and Colorists, Vol. 21, No. 3, March 1989, p17.
14.13 For prints where the singling out of zones too little to test with the standard crockmeter is fundamental (see AATCC Method 116, Rotary Vertical Crockmeter Method). Examples tried by both test techniques may indicate disparate outcomes. There is no known connection between’s the two strategies.
14.14 A mechanized electronic reviewing framework might be utilized the length of the framework has been exhibited to give comes about that are equivalent to and give equivalent or preferable repeatability and reproducibility over an accomplished grader performing visual assessment.
14.15 The accuracy of this test technique is reliant on the consolidated changeability of the material being tried, the test strategy itself, and the assessment method used.
14.15.1 The accuracy explanation in Section 13 was produced from results acquired by visual assessment (EP 2 and EP 8).
14.15.2 It is normal that the utilization of instrumental assessment strategies (EP 12) will bring about more noteworthy accuracy than that gotten from visual assessments.
Additional data about Crockmeter (such as crockmeter price, crockmeter manual, and so on) are accessible on the TESTEX website at http://www.testextextile.com/item/electronic-crockmeter-tf411/.
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